/[dtapublic]/projs/dtats/trunk/projs/20161007_filehash/filehash.c
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Reorganization.
1 dashley 13 //----------------------------------------------------------------------------------------------------
2     //FILEHASH--Calculates the SHA-512 cryptographic hash (also known as a message
3     // digest) of computer files, as defined by FIPS 180-3.
4     //Copyright (C) 2010, David T. Ashley.
5     //
6     //This program is free software: you can redistribute it and/or modify
7     //it under the terms of the GNU General Public License as published by
8     //the Free Software Foundation, either version 3 of the License, or
9     //(at your option) any later version.
10     //
11     //This program is distributed in the hope that it will be useful,
12     //but WITHOUT ANY WARRANTY; without even the implied warranty of
13     //MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14     //GNU General Public License for more details.
15     //
16     //You should have received a copy of the GNU General Public License
17     //along with this program. If not, see <http://www.gnu.org/licenses/>.
18     //(A copy of the GNU General Public License, Version 3 is provided at
19     //the end of this source file.)
20     //
21     //David T. Ashley can be contacted at DASHLEY@GMAIL.COM and/or at
22     //P.O. Box 918, Marshall MI 49068.
23     //----------------------------------------------------------------------------------------------------
24     #include <windows.h>
25     #include <commdlg.h>
26    
27     #include <assert.h>
28     #include <process.h>
29     #include <stdio.h>
30    
31     #include "resource.h"
32    
33    
34     #define FILEHASH_MAXFILES (200)
35     //Maximum number of files that will be processed and displayed.
36     //Limited to avoid filling up the edit control's buffer.
37    
38     #define FILEHASH_DISPBUFLEN (55000)
39     //The point at which we say the edit control buffer has too
40     //many characters in it.
41    
42     #define FILEHASH_FILE_READ_BUF_SIZE (0x10000)
43     //The number of bytes for each read buffer. It is difficult to know
44     //how to size this value. On one hand, larger is better, as it
45     //enables the disk to operate in blocks. On the other hand, too
46     //large is probably not a good idea, as it will take a lot of
47     //time to fill the buffer (several disk seeks). Suspect that 16K-64K
48     //is about the optimum, but may go larger, anyway.
49    
50     static char FILEHASH_dialog_file_open_buffer[15000];
51     //Buffer from the "open files" dialog box, for it to store results
52     //in.
53    
54     static char FILEHASH_dispbuf[FILEHASH_DISPBUFLEN+1];
55     //The buffer which holds the contents of the edit control (the main control, the
56     //text box). This is a mirror buffer, probably not a very efficient way of doing
57     //things.
58    
59     static int FILEHASH_use_sound = 1;
60     //Remembers the state of the "use sound" option. Default is YES.
61    
62     static int FILEHASH_always_on_top = 1;
63     //Remembers whether the main window should always be on top.
64     //This can be annoying in some contexts, so it can be turned off.
65    
66     #define WM_USER_EV_CHILD_THREAD_PROGRESS (WM_USER + 1)
67     //The child thread has progress to report (updated information that
68     //can be used by the parent).
69    
70     #define WM_USER_EV_CHILD_THREAD_ENDING (WM_USER + 2)
71     //The child thread is reporting that it is ending. After this event is
72     //posted for the parent, there may be some delay until the thread is actually
73     //terminated, so additional OS interaction is required to know the thread
74     //is actually dead.
75    
76     static char FILEHASH_szAppName[] = "FileHash";
77     //The application name.
78    
79     static WNDPROC FILEHASH_old_win_edit_handler = NULL;
80     //The old edit control handler. This is used to remember the function pointer,
81     //in order to subclass the behavior, because we must catch the drop files event.
82    
83     static volatile int FILEHASH_thread_abort_request = 0;
84     //This is set TRUE by the main thread if the child thread
85     //should abort. This means the application will terminate
86     //(this is the only reason for setting this flag). This
87     //variable is set by the main thread and read by the
88     //child thread.
89    
90     static DWORD FILEHASH_parent_thread_id = 0;
91     //The thread ID of the parent obtained using the
92     //GetCurrentThreadId() call. The child needs to know this
93     //in order to post a message.
94    
95     static HWND FILEHASH_parent_thread_main_window_handle = 0;
96     //Window handle of main window.
97    
98     static int FILEHASH_child_thread_is_active = 0;
99     //Set TRUE when the child thread is kicked off. Set
100     //FALSE when a message from the child thread is received
101     //indicating that the thread has terminated and when the
102     //thread is confirmed dead. This variable is used only
103     //by the main thread.
104    
105     static HANDLE FILEHASH_child_handle = 0;
106     //The handle of the child process. This is only valid
107     //if a thread is active. This variable is used only
108     //by the main thread to check on status.
109    
110     static unsigned char FILEHASH_file_read_buf[FILEHASH_FILE_READ_BUF_SIZE];
111     //File read buffer for I/O.
112    
113     struct FILEHASH_FileInfoStructPerFile
114     {
115     volatile char fpath[MAX_PATH + 1];
116     //The full path to the file, which should be recognized by the operating system.
117     //If this string is empty, it is a signal that no file is in this slot.
118     volatile int is_directory_valid;
119     //TRUE if the is_directory flag is assigned by the child process and so the
120     //parent can rely on it.
121     volatile int is_directory_error;
122     //TRUE if the child process could not obtain directory information.
123     volatile int is_directory;
124     //TRUE if the file is actually a directory. This means it cannot be processed.
125     volatile int file_size_valid;
126     //TRUE if file size has been assigned by child (or an attempt to assign it was made).
127     volatile int file_size_error;
128     //There was an error in the attempt to obtain file size.
129     volatile unsigned __int64 file_size;
130     //The number of bytes in the file.
131     volatile int sha512_valid;
132     //TRUE if the SHA512 is valid or an attempt was made.
133     volatile char sha512[200];
134     //A string representation of the SHA512 or else an error message from the child.
135     //An SHA-512 should be 129 characters long (128 characters for the hash and 1 for
136     //the terminating 0).
137     };
138    
139     //Aggregated information about all of the files for which a hash is calculated.
140     //
141     struct FILEHASH_FileInfoStruct
142     {
143     volatile struct FILEHASH_FileInfoStructPerFile file_info[FILEHASH_MAXFILES];
144     volatile int terminated_normally;
145     volatile int aborted;
146     };
147    
148    
149     volatile struct FILEHASH_FileInfoStruct FILEHASH_file_info;
150     //This is the major structure that holds file information. Here are the three
151     //roles it fills:
152     //
153     // a)The parent thread fills in this information in preparation for starting
154     // up the child thread.
155     //
156     // b)The child thread fills in the information (file size, SHA-512) as it
157     // goes down this list, and notifies the parent thread with an event,
158     // which causes the updating of displayed information.
159     //
160     // c)After the child thread is finished with all files, another event is sent
161     // to indicate this.
162    
163    
164     //Function prototypes, to be sure no miscompilations where the compiled call doesn't match the
165     //compiled function.
166     int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow);
167     LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;
168     static unsigned __stdcall FILEHASH_ChildThreadFunc(void *pArguments);
169     static void FILEHASH_ChildThreadHardSyncStop(void);
170     static void FILEHASH_ChildThreadStart(void);
171     static void FILEHASH_MakeGenericSound(void);
172    
173    
174     //Maps from a nibble to the corresponding ASCII hexadecimal digit.
175     //
176     char CF_nibble_to_lc_hex_digit(int nibble)
177     {
178     switch (nibble & 0x0F)
179     {
180     case 0:
181     return('0');
182     break;
183     case 1:
184     return('1');
185     break;
186     case 2:
187     return('2');
188     break;
189     case 3:
190     return('3');
191     break;
192     case 4:
193     return('4');
194     break;
195     case 5:
196     return('5');
197     break;
198     case 6:
199     return('6');
200     break;
201     case 7:
202     return('7');
203     break;
204     case 8:
205     return('8');
206     break;
207     case 9:
208     return('9');
209     break;
210     case 10:
211     return('a');
212     break;
213     case 11:
214     return('b');
215     break;
216     case 12:
217     return('c');
218     break;
219     case 13:
220     return('d');
221     break;
222     case 14:
223     return('e');
224     break;
225     case 15:
226     return('f');
227     break;
228     default:
229     return('?');
230     break;
231     }
232     }
233    
234    
235     //Returns TRUE if the passed string seems to be a
236     //valid unsigned integer (without commas) or FALSE
237     //otherwise.
238     //
239     int BSF_is_uint_wo_commas(const char *arg)
240     {
241     if (!*arg)
242     return(0);
243    
244     if (arg[0] == '0')
245     {
246     if (arg[1])
247     {
248     return(0);
249     }
250     else
251     {
252     return(1);
253     }
254     }
255     else
256     {
257     while (*arg)
258     {
259     if ((*arg < '0') || (*arg > '9'))
260     return(0);
261     arg++;
262     }
263    
264     return(1);
265     }
266     }
267    
268    
269     //Adds commas (in the traditional place) to a string that represents an unsigned integer.
270     //
271     void BSF_commanate(char *s)
272     {
273     int l;
274     int ncommas;
275     char *putpt, *getpt;
276     int ndigits;
277    
278     //If the leading character on the string is a
279     //'-', bump the pointer. Then everything
280     //else applies as for an unsigned.
281     if (*s == '-')
282     s++;
283    
284     //Be sure the string currently meets the syntax for
285     //a signed integer. If not, don't even touch it.
286     if (!BSF_is_uint_wo_commas(s))
287     return;
288    
289     //Get the length of the current string.
290     l = strlen(s);
291    
292     //Let's agree, just in case something slipped through
293     //the cracks, that zero length strings are not of
294     //interest to us.
295     if (l==0)
296     return;
297    
298     //The number of commas to add is precisely
299     //(N-1) div 3.
300     if (l==0)
301     ncommas = 0;
302     else
303     ncommas = (l-1)/3;
304    
305     //Walk through the string, adding commas.
306     getpt = s + l - 1;
307     putpt = s + l + ncommas;
308    
309     *putpt = 0; //Write the zero terminator.
310     putpt--;
311    
312     ndigits = 0;
313    
314     while ((putpt > s) && (getpt > s))
315     {
316     *putpt = *getpt;
317     putpt--;
318     getpt--;
319     ndigits++;
320     if (((ndigits % 3) == 0) && (putpt != s))
321     {
322     *putpt = ',';
323     putpt--;
324     }
325    
326     assert((putpt >= s) && (getpt>=s));
327     }
328     }
329    
330    
331     //Fundamental state for forming SHA-512s. Conceptually private to this module.
332     //
333     struct FILEHASH_SHA512_Sha512StateStruct
334     {
335     unsigned __int64 H0, H1, H2, H3, H4, H5, H6, H7;
336     //Directly from FIPS 180-3. In retrospect, this might have
337     //been better implemented as an array.
338     unsigned __int64 bit_count;
339     //The count of bits processed thus far. The algorithm here
340     //works in bytes, not bits, so this is advanced by 8 on
341     //each byte processed. FIPS 180-3 calls for processing
342     //messages up to length 2^128, but for obvious reasons
343     //we don't do that. 2^64-1 bits is in excess of 2^61-1
344     //bytes, or somewhere around 2,000 terabytes. This
345     //isn't a practical limit with current computer technology.
346     unsigned __int64 M[16];
347     //These are the words corresponding to the chars (below). We don't
348     //dare union to extract them because of big-endian/little-endian concerns.
349     //The "M" nomenclature is from FIPS 180-3. At the time the
350     //SHA-512 rounds are done, the chars (below) are converted to words
351     //(this field) so that the rounds can be done using the words.
352     unsigned char buf[128];
353     //We can't proceed to execute a round unless we have the
354     //full 1024 bits = 16 words = 128 bytes of data. We must
355     //buffer it because we can't count on being called with data
356     //blocks that are a multiple of 128. We may have data hanging
357     //around between calls. We fill up this buffer from the low
358     //end, i.e. [0], then [1], then [2], etc.
359     };
360    
361    
362     //Result structure, used to hold result. Caller is allowed to
363     //pick it apart.
364     //
365     struct FILEHASH_SHA512_Sha512ResultStruct
366     {
367     unsigned __int64 sha512_words[8];
368     //Hash in binary form, as the 64-bit integers.
369     char sha512_chars[129];
370     //Zero-terminated string containing character representation
371     //of SHA-512 formed.
372     };
373    
374    
375     //This is a right rotation macro for efficiency. This
376     //macro rotates a 64-bit quantity x right (cyclically) by
377     //n bits. Nomenclature from FIPS 180-3.
378     #define FILEHASH_SHA512_FUNC_ROTR(x, n) (((x) >> (n)) | ((x) << (64-(n))))
379    
380     //This is a right shift macro for efficiency. This
381     //macro shifts a 64-bit quantity x right by
382     //n bits. Nomenclature from FIPS 180-3.
383     #define FILEHASH_SHA512_FUNC_SHR(x, n) ((x) >> (n))
384    
385     //These functions come directly from FIPS 180-3.
386     #define FILEHASH_SHA512_FUNC_CH(x, y, z) (((x) & (y)) ^ (~(x) & (z)))
387     #define FILEHASH_SHA512_FUNC_MAJ(x, y, z) (((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)))
388     #define FILEHASH_SHA512_FUNC_SIGMABIG_0(x) (FILEHASH_SHA512_FUNC_ROTR(x, 28) ^ FILEHASH_SHA512_FUNC_ROTR(x, 34) ^ FILEHASH_SHA512_FUNC_ROTR(x, 39))
389     #define FILEHASH_SHA512_FUNC_SIGMABIG_1(x) (FILEHASH_SHA512_FUNC_ROTR(x, 14) ^ FILEHASH_SHA512_FUNC_ROTR(x, 18) ^ FILEHASH_SHA512_FUNC_ROTR(x, 41))
390     #define FILEHASH_SHA512_FUNC_SIGMASMALL_0(x) (FILEHASH_SHA512_FUNC_ROTR(x, 1) ^ FILEHASH_SHA512_FUNC_ROTR(x, 8) ^ FILEHASH_SHA512_FUNC_SHR(x, 7))
391     #define FILEHASH_SHA512_FUNC_SIGMASMALL_1(x) (FILEHASH_SHA512_FUNC_ROTR(x, 19) ^ FILEHASH_SHA512_FUNC_ROTR(x, 61) ^ FILEHASH_SHA512_FUNC_SHR(x, 6))
392    
393    
394     //Constants, from FIPS 180-3.
395     const unsigned __int64 FILEHASH_SHA512_K[80] =
396     {0x428a2f98d728ae22UL, 0x7137449123ef65cdUL,
397     0xb5c0fbcfec4d3b2fUL, 0xe9b5dba58189dbbcUL,
398     0x3956c25bf348b538UL, 0x59f111f1b605d019UL,
399     0x923f82a4af194f9bUL, 0xab1c5ed5da6d8118UL,
400     0xd807aa98a3030242UL, 0x12835b0145706fbeUL,
401     0x243185be4ee4b28cUL, 0x550c7dc3d5ffb4e2UL,
402     0x72be5d74f27b896fUL, 0x80deb1fe3b1696b1UL,
403     0x9bdc06a725c71235UL, 0xc19bf174cf692694UL,
404     0xe49b69c19ef14ad2UL, 0xefbe4786384f25e3UL,
405     0x0fc19dc68b8cd5b5UL, 0x240ca1cc77ac9c65UL,
406     0x2de92c6f592b0275UL, 0x4a7484aa6ea6e483UL,
407     0x5cb0a9dcbd41fbd4UL, 0x76f988da831153b5UL,
408     0x983e5152ee66dfabUL, 0xa831c66d2db43210UL,
409     0xb00327c898fb213fUL, 0xbf597fc7beef0ee4UL,
410     0xc6e00bf33da88fc2UL, 0xd5a79147930aa725UL,
411     0x06ca6351e003826fUL, 0x142929670a0e6e70UL,
412     0x27b70a8546d22ffcUL, 0x2e1b21385c26c926UL,
413     0x4d2c6dfc5ac42aedUL, 0x53380d139d95b3dfUL,
414     0x650a73548baf63deUL, 0x766a0abb3c77b2a8UL,
415     0x81c2c92e47edaee6UL, 0x92722c851482353bUL,
416     0xa2bfe8a14cf10364UL, 0xa81a664bbc423001UL,
417     0xc24b8b70d0f89791UL, 0xc76c51a30654be30UL,
418     0xd192e819d6ef5218UL, 0xd69906245565a910UL,
419     0xf40e35855771202aUL, 0x106aa07032bbd1b8UL,
420     0x19a4c116b8d2d0c8UL, 0x1e376c085141ab53UL,
421     0x2748774cdf8eeb99UL, 0x34b0bcb5e19b48a8UL,
422     0x391c0cb3c5c95a63UL, 0x4ed8aa4ae3418acbUL,
423     0x5b9cca4f7763e373UL, 0x682e6ff3d6b2b8a3UL,
424     0x748f82ee5defb2fcUL, 0x78a5636f43172f60UL,
425     0x84c87814a1f0ab72UL, 0x8cc702081a6439ecUL,
426     0x90befffa23631e28UL, 0xa4506cebde82bde9UL,
427     0xbef9a3f7b2c67915UL, 0xc67178f2e372532bUL,
428     0xca273eceea26619cUL, 0xd186b8c721c0c207UL,
429     0xeada7dd6cde0eb1eUL, 0xf57d4f7fee6ed178UL,
430     0x06f067aa72176fbaUL, 0x0a637dc5a2c898a6UL,
431     0x113f9804bef90daeUL, 0x1b710b35131c471bUL,
432     0x28db77f523047d84UL, 0x32caab7b40c72493UL,
433     0x3c9ebe0a15c9bebcUL, 0x431d67c49c100d4cUL,
434     0x4cc5d4becb3e42b6UL, 0x597f299cfc657e2aUL,
435     0x5fcb6fab3ad6faecUL, 0x6c44198c4a475817UL};
436    
437    
438     //Initializes an SHA-512 state structure in preparation for adding data.
439     //
440     void FILEHASH_SHA512_Sha512StateStructOpen(struct FILEHASH_SHA512_Sha512StateStruct *arg)
441     {
442     memset(arg, 0, sizeof(struct FILEHASH_SHA512_Sha512StateStruct));
443     //Set everything to zero--processed bitcount set to zero.
444    
445     //This assignment comes directly from FIPS 180-3.
446     arg->H0 = 0x6a09e667f3bcc908UL;
447     arg->H1 = 0xbb67ae8584caa73bUL;
448     arg->H2 = 0x3c6ef372fe94f82bUL;
449     arg->H3 = 0xa54ff53a5f1d36f1UL;
450     arg->H4 = 0x510e527fade682d1UL;
451     arg->H5 = 0x9b05688c2b3e6c1fUL;
452     arg->H6 = 0x1f83d9abfb41bd6bUL;
453     arg->H7 = 0x5be0cd19137e2179UL;
454     }
455    
456    
457     //Copies the byte buffer to the word buffer within the state block.
458     //This is done in a way which hides big-endian/little-endian concerns.
459     //
460     static void FILEHASH_SHA512_CopyBytesToWords(struct FILEHASH_SHA512_Sha512StateStruct *arg)
461     {
462     unsigned int i;
463    
464     assert(arg != NULL);
465    
466     //Copy the buffer contents into the words. We need to be careful
467     //to do this correctly, because of big-endian/little-endian concerns.
468     //From FIPS 180-3 (alluded to, not really stated), the message is
469     //loaded in from M[0] down to M[15]. Additionally, per the other
470     //conventions in the document, the first byte is uppermost in each
471     //word.
472     for (i=0; i<16; i++)
473     {
474     assert((i * 8 + 7) < 128);
475    
476     arg->M[i] = (((unsigned __int64)(arg->buf[i*8+0])) << 56)
477     +
478     (((unsigned __int64)(arg->buf[i*8+1])) << 48)
479     +
480     (((unsigned __int64)(arg->buf[i*8+2])) << 40)
481     +
482     (((unsigned __int64)(arg->buf[i*8+3])) << 32)
483     +
484     (((unsigned __int64)(arg->buf[i*8+4])) << 24)
485     +
486     (((unsigned __int64)(arg->buf[i*8+5])) << 16)
487     +
488     (((unsigned __int64)(arg->buf[i*8+6])) << 8)
489     +
490     (((unsigned __int64)(arg->buf[i*8+7])));
491     }
492     }
493    
494    
495     //Copies the buffer of words into a string buffer of string length 128, and also places
496     //the zero terminator, which means that the string supplied by the caller must be of size
497     //129 or larger.
498     //
499     static void FILEHASH_SHA512_CopyWordsToStringBuffer(struct FILEHASH_SHA512_Sha512ResultStruct *arg)
500     {
501     unsigned int i, j;
502     unsigned char *puc;
503     unsigned __int64 woi;
504    
505     assert(arg != NULL);
506    
507     //Copy the buffer contents into the words. We need to be careful
508     //to do this correctly, because of big-endian/little-endian concerns.
509     //From FIPS 180-3 (alluded to, not really stated), the message is
510     //loaded in from M[0] down to M[15]. Additionally, per the other
511     //conventions in the document, the first byte is uppermost in each
512     //word.
513     for (i=0; i<8; i++)
514     {
515     woi = arg->sha512_words[i];
516    
517     //Form a pointer to the buffer location of interest. We work
518     //backwards.
519     puc = (unsigned char *)(arg->sha512_chars) + (i * 16) + 15;
520    
521     //Fill in the buffer.
522     for (j=0; j<16; j++)
523     {
524     *puc = (unsigned char)CF_nibble_to_lc_hex_digit((int)(woi & 0xF));
525     woi >>= 4;
526     puc--;
527     }
528     }
529    
530     //Place the zero string terminator.
531     arg->sha512_chars[128] = 0;
532     }
533    
534    
535     //Do the SHA-512 rounds as specified by FIPS 180-3.
536     //
537     static void FILEHASH_SHA512_DoSha512Rounds(struct FILEHASH_SHA512_Sha512StateStruct *arg)
538     {
539     int i;
540     //Iteration variable.
541     unsigned __int64 T1, T2;
542     //Temporary variables. Nomenclature is from FIPS 180-3.
543     unsigned __int64 M[16];
544     //Buffer of message block to avoid repeated dereferences.
545     unsigned __int64 H[8];
546     //Buffer of hash state to avoid repeated dereferences.
547     unsigned __int64 W[80];
548     //Working variable. Nomenclature directly from FIPS 180-3.
549     unsigned __int64 a, b, c, d, e, f, g, h;
550     //Nomenclature above directly from FIPS 180-3.
551    
552     assert(arg != NULL);
553    
554     //Copy bytes into words.
555     FILEHASH_SHA512_CopyBytesToWords(arg);
556    
557     //Copy out the message buffer for speed. This should avoid repeated
558     //dereferences.
559     M[ 0] = arg->M[ 0];
560     M[ 1] = arg->M[ 1];
561     M[ 2] = arg->M[ 2];
562     M[ 3] = arg->M[ 3];
563     M[ 4] = arg->M[ 4];
564     M[ 5] = arg->M[ 5];
565     M[ 6] = arg->M[ 6];
566     M[ 7] = arg->M[ 7];
567     M[ 8] = arg->M[ 8];
568     M[ 9] = arg->M[ 9];
569     M[10] = arg->M[10];
570     M[11] = arg->M[11];
571     M[12] = arg->M[12];
572     M[13] = arg->M[13];
573     M[14] = arg->M[14];
574     M[15] = arg->M[15];
575    
576     //Copy out the hash state for speed. This should avoid repeated dereferences.
577     H[0] = arg->H0;
578     H[1] = arg->H1;
579     H[2] = arg->H2;
580     H[3] = arg->H3;
581     H[4] = arg->H4;
582     H[5] = arg->H5;
583     H[6] = arg->H6;
584     H[7] = arg->H7;
585    
586     //Prepare the message schedule. The nomenclature comes directly from FIPS 180-3.
587     W[ 0] = M[ 0];
588     W[ 1] = M[ 1];
589     W[ 2] = M[ 2];
590     W[ 3] = M[ 3];
591     W[ 4] = M[ 4];
592     W[ 5] = M[ 5];
593     W[ 6] = M[ 6];
594     W[ 7] = M[ 7];
595     W[ 8] = M[ 8];
596     W[ 9] = M[ 9];
597     W[10] = M[10];
598     W[11] = M[11];
599     W[12] = M[12];
600     W[13] = M[13];
601     W[14] = M[14];
602     W[15] = M[15];
603    
604     for (i=16; i<80; i++)
605     {
606     W[i] = FILEHASH_SHA512_FUNC_SIGMASMALL_1(W[i-2])
607     + W[i-7]
608     + FILEHASH_SHA512_FUNC_SIGMASMALL_0(W[i-15])
609     + W[i-16];
610     }
611    
612     //Initialize the 8 working variables as specified in FIPS 180-3.
613     a = H[0];
614     b = H[1];
615     c = H[2];
616     d = H[3];
617     e = H[4];
618     f = H[5];
619     g = H[6];
620     h = H[7];
621    
622     //Perform the rounds as specified in FIPS 180-3. Nomenclature below comes from
623     //FIPS 180-3.
624     for (i=0; i<80; i++)
625     {
626     T1 = h
627     + FILEHASH_SHA512_FUNC_SIGMABIG_1(e)
628     + FILEHASH_SHA512_FUNC_CH(e, f, g)
629     + FILEHASH_SHA512_K[i]
630     + W[i];
631     //
632     T2 = FILEHASH_SHA512_FUNC_SIGMABIG_0(a)
633     + FILEHASH_SHA512_FUNC_MAJ(a, b, c);
634     //
635     h = g;
636     //
637     g = f;
638     //
639     f = e;
640     //
641     e = d + T1;
642     //
643     d = c;
644     //
645     c = b;
646     //
647     b = a;
648     //
649     a = T1 + T2;
650     }
651    
652     //Compute the next hash value. The nomenclature comes from FIPS 180-3.
653     H[0] = a + H[0];
654     H[1] = b + H[1];
655     H[2] = c + H[2];
656     H[3] = d + H[3];
657     H[4] = e + H[4];
658     H[5] = f + H[5];
659     H[6] = g + H[6];
660     H[7] = h + H[7];
661    
662     //Place the local variables back in the structure. This the only state that
663     //gets preserved between the operation of doing the rounds.
664     arg->H0 = H[0];
665     arg->H1 = H[1];
666     arg->H2 = H[2];
667     arg->H3 = H[3];
668     arg->H4 = H[4];
669     arg->H5 = H[5];
670     arg->H6 = H[6];
671     arg->H7 = H[7];
672     }
673    
674    
675     //Adds a block of data to the SHA-512 structure. Zero length is allowed.
676     //
677     void FILEHASH_SHA512_Sha512StateStructAddData(struct FILEHASH_SHA512_Sha512StateStruct *arg,
678     void *pointer_in,
679     unsigned len)
680     {
681     unsigned int low_32;
682     unsigned int byte_offset;
683     unsigned char *data;
684    
685     assert((len == 0) || (arg != NULL));
686     assert(pointer_in != NULL);
687    
688     data = (unsigned char *)pointer_in;
689     //It is easier to do it this way, rather than cast all the time.
690    
691     low_32 = (unsigned int)arg->bit_count;
692     //Copy off the least significant bits. Easier to do once. We only
693     //need the 32 least significant because the block size is 0 modulo 1024.
694    
695     byte_offset = low_32 >> 3;
696     //This gives our byte offset, up to 500+Mb or so.
697    
698     while(len--)
699     {
700     //We process rounds AFTER a byte is added to the buffer. So
701     //it is always safe to add a byte first.
702     arg->buf[byte_offset & 0x7F] = *data;
703    
704     //Nothing to do unless this was the final byte of the buffer.
705     if ((byte_offset & 0x7F) == 127)
706     {
707     FILEHASH_SHA512_DoSha512Rounds(arg);
708     }
709    
710     //Increment.
711     data++;
712     byte_offset++;
713     arg->bit_count += 8;
714     }
715     }
716    
717    
718     //Closes the SHA-512 structure and places the SHA-512 result into the result structure.
719     //After this operation, state is destroyed and no further data may be added.
720     //
721     void FILEHASH_SHA512_Sha512StateStructClose(struct FILEHASH_SHA512_Sha512StateStruct *state,
722     struct FILEHASH_SHA512_Sha512ResultStruct *result)
723     {
724     unsigned __int64 msglen;
725     //Used to hold message length before we pad the message.
726     unsigned char c80 = 0x80;
727     //Used to append the "1" per FIPS 180-3.
728     unsigned char c00 = 0x00;
729     //Used to add 0's per FIPS 180-3.
730     unsigned char length_buf[16];
731     //Buffer used to form the message length and append it to the message per FIPS 180-3.
732    
733     //Be sure the input pointers aren't obviously invalid.
734     assert(state != NULL);
735     assert(result != NULL);
736    
737     //Snapshot the message length. We'll be changing it when we pad the message.
738     msglen = state->bit_count;
739    
740     //Add the required "1" to the end of the message, per FIPS 180-3. Because
741     //this software module only allows the addition of bytes (not bits), adding the
742     //"1" will always involve adding the byte 0x80.
743     FILEHASH_SHA512_Sha512StateStructAddData(state, &c80, 1);
744    
745     //Add enough 0's to the message so that we have exactly room for 16 bytes (128 bits)
746     //of length information at the end of the message.
747     while ((state->bit_count & 0x3FF) != 896)
748     FILEHASH_SHA512_Sha512StateStructAddData(state, &c00, 1);
749    
750     //Calculate the length as a series of bytes.
751     length_buf[ 0] = 0;
752     length_buf[ 1] = 0;
753     length_buf[ 2] = 0;
754     length_buf[ 3] = 0;
755     length_buf[ 4] = 0;
756     length_buf[ 5] = 0;
757     length_buf[ 6] = 0;
758     length_buf[ 7] = 0;
759     length_buf[ 8] = (unsigned char)((msglen >> 56) & 0xFF);
760     length_buf[ 9] = (unsigned char)((msglen >> 48) & 0xFF);
761     length_buf[10] = (unsigned char)((msglen >> 40) & 0xFF);
762     length_buf[11] = (unsigned char)((msglen >> 32) & 0xFF);
763     length_buf[12] = (unsigned char)((msglen >> 24) & 0xFF);
764     length_buf[13] = (unsigned char)((msglen >> 16) & 0xFF);
765     length_buf[14] = (unsigned char)((msglen >> 8) & 0xFF);
766     length_buf[15] = (unsigned char)((msglen) & 0xFF);
767    
768     //Add the length to the message. This should work out to generate the
769     //final manipulation round.
770     FILEHASH_SHA512_Sha512StateStructAddData(state, length_buf, 16);
771    
772     //Copy the words from the state vector to the result vector.
773     result->sha512_words[0] = state->H0;
774     result->sha512_words[1] = state->H1;
775     result->sha512_words[2] = state->H2;
776     result->sha512_words[3] = state->H3;
777     result->sha512_words[4] = state->H4;
778     result->sha512_words[5] = state->H5;
779     result->sha512_words[6] = state->H6;
780     result->sha512_words[7] = state->H7;
781    
782     //Form a string from the hash vector.
783     FILEHASH_SHA512_CopyWordsToStringBuffer(result);
784    
785     //Destroy the state, which may contain sensitive information.
786     memset(state, 0, sizeof(struct FILEHASH_SHA512_Sha512StateStruct));
787     }
788    
789    
790     //Main function for Windows.
791     //
792     int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
793     PSTR szCmdLine, int iCmdShow)
794     {
795     HWND hwnd ;
796     HMENU hmenu;
797     MSG msg ;
798     WNDCLASS wndclass ;
799    
800     //Store our current parent thread ID. The child process will need
801     //to know this to post a message. This is expected to be
802     //invariant for the life of the program.
803     FILEHASH_parent_thread_id = GetCurrentThreadId();
804    
805     //Zero out the file information block.
806     memset((char *)&FILEHASH_file_info, 0, sizeof(FILEHASH_file_info));
807    
808     wndclass.style = CS_HREDRAW | CS_VREDRAW ;
809     wndclass.lpfnWndProc = WndProc ;
810     wndclass.cbClsExtra = 0 ;
811     wndclass.cbWndExtra = 0 ;
812     wndclass.hInstance = hInstance ;
813     wndclass.hIcon = LoadIcon (hInstance, MAKEINTRESOURCE(IDI_ICON)) ;
814     wndclass.hCursor = LoadCursor (NULL, IDC_ARROW) ;
815     wndclass.hbrBackground = (HBRUSH) (COLOR_BTNFACE+1) ;
816     wndclass.lpszMenuName = NULL ;
817     wndclass.lpszClassName = FILEHASH_szAppName ;
818    
819     if (!RegisterClass (&wndclass))
820     {
821     MessageBox (NULL,
822     TEXT ("Error code from RegisterClass() Win32 API function. \nThe most probable cause is an incompatible operating system."),
823     FILEHASH_szAppName,
824     MB_ICONERROR) ;
825     return 0 ;
826     }
827    
828     //We need to do some voodoo to figure out how large to make the main window.
829     //The feeling is that the window should be as small as possible to display the
830     //results from an individual file (the most common application), and if the user
831     //wants it bigger it can be resized. Three lines are required (file name, file
832     //size, and SHA-512), so that needs to be the height. A file
833     //SHA-512 is 512 bits = 128 characters. In addition, there is the constraint that we
834     //cannot go beyond the width and height of a screen. The guess below is quite
835     //crude, assuming that the edit box has a larger font, etc.
836     {
837     int initial_width = 0;
838     int initial_height = 0;
839    
840     //Get a crude measure of how big text is.
841     initial_width = LOWORD(GetDialogBaseUnits());
842     initial_height = HIWORD(GetDialogBaseUnits());
843    
844     //Dope it up linearly.
845     initial_width = (initial_width * 1500)/10;
846     initial_height = (initial_height * 150)/10;
847    
848     {
849     int temp;
850    
851     //Be sure nothing is bigger than 2/3 screen dimensions.
852     temp = (GetSystemMetrics(SM_CXFULLSCREEN) * 2) / 3;
853     if (initial_width > temp)
854     initial_width = temp;
855     temp = (GetSystemMetrics(SM_CYFULLSCREEN) * 2) / 3;
856     if (initial_height > temp)
857     initial_height = temp;
858     }
859    
860     //Load up the menu resources. I have verified in documentation that this will be destroyed
861     //automatically.
862     hmenu = LoadMenu(hInstance, MAKEINTRESOURCE(IDR_FILEHASH));
863    
864     //Create the window. The "Ex" call is used to make it a topmost window.
865     hwnd = CreateWindowEx (
866     WS_EX_TOPMOST,
867     FILEHASH_szAppName, // window class name
868     TEXT ("FileHash"), // window caption
869     WS_OVERLAPPEDWINDOW, // window style
870     CW_USEDEFAULT, // initial x position
871     CW_USEDEFAULT, // initial y position
872     initial_width, // initial x size
873     initial_height, // initial y size
874     NULL, // parent window handle
875     hmenu, // window menu handle
876     hInstance, // program instance handle
877     NULL) ; // creation parameters
878     }
879    
880    
881     FILEHASH_parent_thread_main_window_handle = hwnd;
882    
883     //This is standard code from Petzold's book. Don't know _exactly_ what it does, but
884     //every Windows program seems to have it.
885     ShowWindow (hwnd, iCmdShow) ;
886     UpdateWindow (hwnd) ;
887    
888     while (GetMessage (&msg, NULL, 0, 0))
889     {
890     TranslateMessage (&msg) ;
891     DispatchMessage (&msg) ;
892     }
893    
894     return msg.wParam ;
895     }
896    
897    
898     //This is the subclass WndProc. This had to be done to allow the edit
899     //control to catch the WM_DROPFILES event.
900     //
901     LRESULT CALLBACK FILEHASH_ReplacementEditProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
902     {
903     static int iDeltaPerLine = 120, iAccumDelta = 0;
904     //These are for mouse wheel logic. It may happen in the future that more
905     //precise mice without notches are introduced.
906    
907     //We need to watch for the drop target notification message, and take action
908     //in that case.
909     switch(message)
910     {
911     case WM_DROPFILES:
912     {
913     int iFiles;
914     int i;
915     HDROP hDropInfo = (HANDLE)wParam;
916    
917     //Do a hard sync stop on the child thread. This should not take
918     //very long. A new drag'n'drop event will just cause restart
919     //with the new set of files.
920     FILEHASH_ChildThreadHardSyncStop();
921    
922     //Zero out the file information area and the text buffer mirror.
923     memset((char *)&FILEHASH_file_info, 0, sizeof(FILEHASH_file_info));
924     FILEHASH_dispbuf[0] = 0;
925    
926     // Get the number of files and folders that were dropped.
927     iFiles = DragQueryFile (hDropInfo, (DWORD)(-1), (LPSTR)NULL, 0);
928    
929     //Copy the paths to the right buffer area.
930     for (i=0; (i<iFiles) && (i<FILEHASH_MAXFILES); i++)
931     {
932     DragQueryFile (hDropInfo, i, (LPSTR)(FILEHASH_file_info.file_info[i].fpath), MAX_PATH);
933     }
934    
935     //Start up the child thread.
936     FILEHASH_ChildThreadStart();
937    
938     break;
939     }
940     case WM_MOUSEWHEEL:
941     {
942     iAccumDelta += (short) HIWORD (wParam);
943    
944     while (iAccumDelta >= iDeltaPerLine)
945     {
946     SendMessage(hwnd, WM_VSCROLL, SB_PAGEUP, 0);
947     iAccumDelta -= iDeltaPerLine;
948     //iAccumDelta = 0;
949     }
950    
951     while (iAccumDelta <= -iDeltaPerLine)
952     {
953     SendMessage(hwnd, WM_VSCROLL, SB_PAGEDOWN, 0);
954     iAccumDelta += iDeltaPerLine;
955     //iAccumDelta = 0;
956     }
957    
958     break;
959     }
960     }
961    
962     //Call the old Window procedure.
963     return (CallWindowProc(FILEHASH_old_win_edit_handler, hwnd, message, wParam, lParam));
964     }
965    
966    
967     //Stages the display buffer in preparation for outputting it out
968     //to the edit child window. This function generally interacts
969     //with the file information data structure even while the
970     //child thread is running. This is OK, as race conditions are
971     //covered. Essentially, as the child thread proceeds, it updates
972     //data then afterwards flags it as valid. This function
973     //never proceeds into invalid data.
974     //
975     static void FILEHASH_StageDisplayBuffer(void)
976     {
977     int dispbufidx;
978     int nfiles;
979     int len;
980     int i;
981     char buf[2*MAX_PATH+200];
982    
983     //Count the number of files queued, and put that in the buffer.
984     dispbufidx = 0;
985     nfiles=0;
986     for (i=0; i<FILEHASH_MAXFILES; i++)
987     {
988     if (FILEHASH_file_info.file_info[i].fpath[0])
989     {
990     nfiles++;
991     }
992     else
993     {
994     break;
995     }
996     }
997     sprintf_s(buf, sizeof(buf), "Files to signature: %d.\x0d\x0a", nfiles);
998     len = strlen(buf);
999     if ((len + dispbufidx + 2) < FILEHASH_DISPBUFLEN)
1000     {
1001     strcpy_s(FILEHASH_dispbuf+dispbufidx, sizeof(FILEHASH_dispbuf) - dispbufidx,buf);
1002     dispbufidx += len;
1003     }
1004    
1005     //Loop through and output the information for each file.
1006     for (i=0; i<FILEHASH_MAXFILES; i++)
1007     {
1008     if ((FILEHASH_file_info.file_info[i].fpath[0]) && (FILEHASH_file_info.file_info[i].is_directory_valid))
1009     {
1010     sprintf_s(buf, sizeof(buf), "--------------------\x0d\x0a");
1011     len = strlen(buf);
1012     if ((len + dispbufidx + 2) < FILEHASH_DISPBUFLEN)
1013     {
1014     strcpy_s(FILEHASH_dispbuf+dispbufidx, sizeof(FILEHASH_dispbuf)-dispbufidx, buf);
1015     dispbufidx += len;
1016     }
1017    
1018     sprintf_s(buf, sizeof(buf), "[%03d/%03d] %s\x0d\x0a", i+1, nfiles, FILEHASH_file_info.file_info[i].fpath);
1019     len = strlen(buf);
1020     if ((len + dispbufidx + 2) < FILEHASH_DISPBUFLEN)
1021     {
1022     strcpy_s(FILEHASH_dispbuf+dispbufidx, sizeof(FILEHASH_dispbuf)-dispbufidx, buf);
1023     dispbufidx += len;
1024     }
1025    
1026     //If the file is actually a directory or there was an error, we can't
1027     //do further processing on it.
1028     if (FILEHASH_file_info.file_info[i].is_directory_error)
1029     {
1030     sprintf_s(buf, sizeof(buf), "\tError obtaining file attributes--cannot process this file.\x0d\x0a");
1031     len = strlen(buf);
1032     if ((len + dispbufidx + 2) < FILEHASH_DISPBUFLEN)
1033     {
1034     strcpy_s(FILEHASH_dispbuf+dispbufidx, sizeof(FILEHASH_dispbuf)-dispbufidx, buf);
1035     dispbufidx += len;
1036     }
1037     }
1038     else if (FILEHASH_file_info.file_info[i].is_directory)
1039     {
1040     sprintf_s(buf, sizeof(buf), "\tThis item is a directory and will not be signatured.\x0d\x0a");
1041     len = strlen(buf);
1042     if ((len + dispbufidx + 2) < FILEHASH_DISPBUFLEN)
1043     {
1044     strcpy_s(FILEHASH_dispbuf+dispbufidx, sizeof(FILEHASH_dispbuf)-dispbufidx, buf);
1045     dispbufidx += len;
1046     }
1047     }
1048     else
1049     {
1050     //This is not a directory. We can print the rest of the
1051     //information.
1052     //
1053     //First, the file size.
1054     if (FILEHASH_file_info.file_info[i].file_size_valid)
1055     {
1056     char buf2[100];
1057    
1058     buf2[0] = 0; //Just in case conversion doesn't go right.
1059     sprintf_s(buf2, sizeof(buf2), "%I64u", FILEHASH_file_info.file_info[i].file_size);
1060     BSF_commanate(buf2);
1061     sprintf_s(buf, sizeof(buf), "\tSize:\t%s\x0d\x0a", buf2);
1062    
1063     len = strlen(buf);
1064     if ((len + dispbufidx + 2) < FILEHASH_DISPBUFLEN)
1065     {
1066     strcpy_s(FILEHASH_dispbuf+dispbufidx, sizeof(FILEHASH_dispbuf)-dispbufidx, buf);
1067     dispbufidx += len;
1068     }
1069     }
1070    
1071     //Now, the SHA512.
1072     if (FILEHASH_file_info.file_info[i].sha512_valid)
1073     {
1074     sprintf_s(buf, sizeof(buf), "\tSHA-512:\t%s\x0d\x0a", FILEHASH_file_info.file_info[i].sha512);
1075     len = strlen(buf);
1076     if ((len + dispbufidx + 2) < FILEHASH_DISPBUFLEN)
1077     {
1078     strcpy_s(FILEHASH_dispbuf+dispbufidx, sizeof(FILEHASH_dispbuf)-dispbufidx, buf);
1079     dispbufidx += len;
1080     }
1081     }
1082     }
1083     }
1084     else
1085     {
1086     break;
1087     }
1088    
1089     }
1090    
1091     //Process the termination condition information.
1092     if (FILEHASH_file_info.aborted)
1093     {
1094     sprintf_s(buf, sizeof(buf), "-------------------- FILE SIGNATURE ABORTED --------------------");
1095     }
1096     else if (FILEHASH_file_info.terminated_normally)
1097     {
1098     sprintf_s(buf, sizeof(buf), "-------------------- FILE SIGNATURE COMPLETE --------------------");
1099     }
1100     else
1101     {
1102     sprintf_s(buf, sizeof(buf), "-------------------- FILE SIGNATURE IN PROGRESS -------------------");
1103     }
1104    
1105     len = strlen(buf);
1106     if ((len + dispbufidx + 2) < FILEHASH_DISPBUFLEN)
1107     {
1108     strcpy_s(FILEHASH_dispbuf+dispbufidx, sizeof(FILEHASH_dispbuf)-dispbufidx, buf);
1109     dispbufidx += len;
1110     }
1111     }
1112    
1113    
1114     //Pushes the display buffer out to the edit control.
1115     //
1116     static int FILEHASH_UpdateEditControl(HWND te_wind)
1117     {
1118     SetWindowText(te_wind, FILEHASH_dispbuf);
1119    
1120     //Must set the buffer position (i.e. the display position) to the end.
1121     //The "/10" assumes that there can't be more than 8 chars or so per line--
1122     //couldn't find a way to go to the end automatically.
1123     SendMessage(te_wind,EM_LINESCROLL,0,FILEHASH_DISPBUFLEN/8);
1124    
1125     return(0);
1126     }
1127    
1128    
1129     //This is the Windows procedure and event loop for the
1130     //main Window.
1131     //
1132     LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
1133     {
1134     HDC hdc ;
1135     PAINTSTRUCT ps ;
1136     static RECT rect ;
1137     static HWND te_wind = 0;
1138    
1139     switch (message)
1140     {
1141     case WM_CREATE:
1142     {
1143     //Need to get the size of our current window so we can create the
1144     //child same size.
1145     //
1146     GetClientRect (hwnd, &rect);
1147    
1148     te_wind = CreateWindow ("EDIT", // window class name
1149     "", // window caption
1150     WS_CHILD|WS_VISIBLE|WS_BORDER|ES_MULTILINE|ES_AUTOVSCROLL|ES_WANTRETURN, // window style
1151     0, // initial x position
1152     0, // initial y position
1153     rect.right, // initial x size
1154     rect.bottom, // initial y size
1155     hwnd, // parent window handle
1156     (HMENU) 1, // window menu handle
1157     ((LPCREATESTRUCT)lParam)->hInstance, // program instance handle
1158     NULL) ; // creation parameters
1159     //Print initial usage instructions.
1160     SetWindowText(te_wind, "FILEHASH, Copyright \xA9 2010 David T. Ashley\x0d\x0a"
1161     "\x0d\x0a"
1162     "This program is provided under the GNU General Public License, Version 3, and comes with ABSOLUTELY NO WARRANTY. "
1163     "This is free software, and you are welcome to redistribute it. For a copy of the source code and license, please write to "
1164     "David T. Ashley (dashley@gmail.com)."
1165     "\x0d\x0a"
1166     "\x0d\x0a"
1167     "To calculate "
1168     "SHA-512 message digests, "
1169     "drag and drop files into this box (from Windows Explorer "
1170     "or a similar application), or use the FILE->OPEN "
1171     "menu selection. Text can be freely selected and "
1172     "copied from this window (select the desired text "
1173     "and use the right mouse button to obtain a popup menu "
1174     "which includes COPY).");
1175    
1176     //Tell Windows that this child is a fair drop target for files.
1177     DragAcceptFiles (te_wind, TRUE);
1178    
1179     //We need to subclass the child window, which is to define a new wndproc
1180     //for it.
1181     FILEHASH_old_win_edit_handler = (WNDPROC) SetWindowLong(te_wind, GWL_WNDPROC, (long) FILEHASH_ReplacementEditProc);
1182    
1183     return 0 ;
1184     }
1185     case WM_SIZE:
1186     {
1187     rect.left = 0;
1188     rect.top = 0;
1189     rect.right = LOWORD(lParam);
1190     rect.bottom = HIWORD(lParam);
1191     MoveWindow(te_wind, 0, 0, rect.right, rect.bottom, TRUE);
1192     return 0;
1193     }
1194     case WM_PAINT:
1195     {
1196     hdc = BeginPaint (hwnd, &ps) ;
1197    
1198     GetClientRect (hwnd, &rect) ;
1199    
1200     EndPaint (hwnd, &ps) ;
1201     return 0 ;
1202     }
1203     case WM_DESTROY:
1204     {
1205     PostQuitMessage (0) ;
1206     FILEHASH_ChildThreadHardSyncStop();
1207     return 0 ;
1208     }
1209     //This is a home-spun event which means that there are files to be processed.
1210     //This is sent once when the drop is initially done and then each time a file
1211     //is processed another event is used to continue the process, until finally
1212     //there are no more files to do.
1213     case WM_USER_EV_CHILD_THREAD_PROGRESS:
1214     {
1215     //Just recalc the mirror buffer and redisplay it.
1216     FILEHASH_StageDisplayBuffer();
1217     FILEHASH_UpdateEditControl(te_wind);
1218     return 0;
1219     }
1220     case WM_USER_EV_CHILD_THREAD_ENDING:
1221     {
1222     HMENU hMenu;
1223    
1224     //Just recalc the mirror buffer and redisplay it.
1225     FILEHASH_StageDisplayBuffer();
1226     FILEHASH_UpdateEditControl(te_wind);
1227     FILEHASH_MakeGenericSound();
1228    
1229     hMenu = GetMenu(FILEHASH_parent_thread_main_window_handle);
1230    
1231     EnableMenuItem(hMenu, ID_ACTIONS_HALTSIGOP, MF_GRAYED);
1232    
1233     return 0;
1234     }
1235     case WM_COMMAND:
1236     {
1237     switch(LOWORD(wParam))
1238     {
1239     case ID_FILE_OPEN_FOR_SIG:
1240     {
1241     OPENFILENAME ofn;
1242     static char szFilter[] = "All Files (*.*)\0*.*\0\0";
1243    
1244     //Set up for the dialog.
1245     FILEHASH_dialog_file_open_buffer[0] = 0; //Be sure that initial name zero'd out.
1246     FILEHASH_dialog_file_open_buffer[1] = 0;
1247    
1248     ofn.lStructSize = sizeof(OPENFILENAME);
1249     ofn.hwndOwner = hwnd ;
1250     ofn.hInstance = NULL ;
1251     ofn.lpstrFilter = szFilter;
1252     ofn.lpstrCustomFilter = NULL ;
1253     ofn.nMaxCustFilter = 0 ;
1254     ofn.nFilterIndex = 0 ;
1255     ofn.lpstrFile = FILEHASH_dialog_file_open_buffer;
1256     ofn.nMaxFile = sizeof(FILEHASH_dialog_file_open_buffer) - 1;
1257     ofn.lpstrFileTitle = NULL;
1258     ofn.nMaxFileTitle = 0;
1259     ofn.lpstrInitialDir = NULL ;
1260     ofn.lpstrTitle = "Open File(s) For Message Digest Calculation" ;
1261     ofn.Flags = OFN_ALLOWMULTISELECT
1262     | OFN_FILEMUSTEXIST
1263     | OFN_HIDEREADONLY
1264     | OFN_NODEREFERENCELINKS
1265     | OFN_PATHMUSTEXIST
1266     | OFN_EXPLORER
1267     | OFN_SHAREAWARE;
1268     ofn.nFileOffset = 0 ;
1269     ofn.nFileExtension = 0 ;
1270     ofn.lpstrDefExt = NULL;
1271     ofn.lCustData = 0L ;
1272     ofn.lpfnHook = NULL ;
1273     ofn.lpTemplateName = NULL ;
1274    
1275     //Zero out the dialog return area buffer.
1276     FILEHASH_dialog_file_open_buffer[0] = 0;
1277     FILEHASH_dialog_file_open_buffer[1] = 0;
1278    
1279     if (GetOpenFileName (&ofn))
1280     {
1281     int dstarridx=0;
1282     int srccharidx=0;
1283    
1284     //There was success and something specified. This means we must
1285     //kill the child thread if it is running.
1286     //Do a hard sync stop on the child thread. This should not take
1287     //very long. A new drag'n'drop event will just cause restart
1288     //with the new set of files.
1289     FILEHASH_ChildThreadHardSyncStop();
1290    
1291     //Zero out the file information area and the text buffer mirror.
1292     memset((char *)&FILEHASH_file_info, 0, sizeof(FILEHASH_file_info));
1293     FILEHASH_dispbuf[0] = 0;
1294    
1295     dstarridx=0;
1296     srccharidx=0;
1297    
1298     //Advance to first string terminator.
1299     while (FILEHASH_dialog_file_open_buffer[srccharidx] != 0)
1300     srccharidx++;
1301    
1302     //In the special case where the double-null is encountered immediately, there is
1303     //only one file, and full path is specified.
1304     //
1305     if (!FILEHASH_dialog_file_open_buffer[srccharidx+1])
1306     {
1307     strcpy_s((char *)FILEHASH_file_info.file_info[0].fpath, sizeof(FILEHASH_file_info.file_info[0].fpath), FILEHASH_dialog_file_open_buffer);
1308     }
1309     else
1310     {
1311     //This is the multiple file case.
1312     while ((dstarridx < FILEHASH_MAXFILES) && (FILEHASH_dialog_file_open_buffer[srccharidx+1]))
1313     {
1314     int len;
1315    
1316     srccharidx++;
1317     strcpy_s((char *)FILEHASH_file_info.file_info[dstarridx].fpath, sizeof(FILEHASH_file_info.file_info[dstarridx].fpath), FILEHASH_dialog_file_open_buffer);
1318    
1319     //Watch out for adding two backslashes. This can happen if the path
1320     //contains only a drive letter ("c:\", for example) so that the OS
1321     //adds a path on.
1322     len = strlen(FILEHASH_dialog_file_open_buffer);
1323     if ((len != 0) && (FILEHASH_dialog_file_open_buffer[len-1]=='\\'))
1324     {
1325     //Do nothing. Watch out in modifying this. The "len != 0" test
1326     //above is to prevent an access violation in the second test--watch
1327     //out when modifying this if-then-else construct.
1328     }
1329     else
1330     {
1331     strcat_s((char *)FILEHASH_file_info.file_info[dstarridx].fpath, sizeof(FILEHASH_file_info.file_info[dstarridx].fpath), "\\");
1332     }
1333     strcat_s((char *)FILEHASH_file_info.file_info[dstarridx].fpath, sizeof(FILEHASH_file_info.file_info[dstarridx].fpath), FILEHASH_dialog_file_open_buffer+srccharidx);
1334     while (FILEHASH_dialog_file_open_buffer[srccharidx] != 0)
1335     srccharidx++;
1336     dstarridx++;
1337     }
1338     }
1339    
1340     //Start up the child thread.
1341     FILEHASH_ChildThreadStart();
1342    
1343     //Redisplay the edit buffer.
1344     FILEHASH_StageDisplayBuffer();
1345     FILEHASH_UpdateEditControl(te_wind);
1346     }
1347    
1348     return 0;
1349     }
1350     case ID_FILE_EXIT:
1351     {
1352     SendMessage(hwnd, WM_CLOSE, 0, 0);
1353     return 0;
1354     }
1355     case ID_ACTIONS_HALTSIGOP:
1356     {
1357     FILEHASH_ChildThreadHardSyncStop();
1358     FILEHASH_MakeGenericSound();
1359     FILEHASH_StageDisplayBuffer();
1360     FILEHASH_UpdateEditControl(te_wind);
1361     return 0;
1362     }
1363     case ID_OPTIONS_USE_SOUND:
1364     {
1365     if (FILEHASH_use_sound)
1366     {
1367     HMENU hMenu;
1368    
1369     hMenu = GetMenu(FILEHASH_parent_thread_main_window_handle);
1370     FILEHASH_use_sound = 0;
1371     CheckMenuItem(hMenu, ID_OPTIONS_USE_SOUND, MF_UNCHECKED);
1372     }
1373     else
1374     {
1375     HMENU hMenu;
1376    
1377     hMenu = GetMenu(FILEHASH_parent_thread_main_window_handle);
1378     FILEHASH_use_sound = 1;
1379     CheckMenuItem(hMenu, ID_OPTIONS_USE_SOUND, MF_CHECKED);
1380     }
1381     return 0;
1382     }
1383     case ID_OPTIONS_WINDOWALWAYSONTOP:
1384     {
1385     if (FILEHASH_always_on_top)
1386     {
1387     HMENU hMenu;
1388    
1389     hMenu = GetMenu(FILEHASH_parent_thread_main_window_handle);
1390     FILEHASH_always_on_top = 0;
1391     CheckMenuItem(hMenu, ID_OPTIONS_WINDOWALWAYSONTOP, MF_UNCHECKED);
1392     SetWindowPos(FILEHASH_parent_thread_main_window_handle,
1393     HWND_NOTOPMOST,
1394     0,
1395     0,
1396     0,
1397     0,
1398     SWP_NOMOVE | SWP_NOSIZE | SWP_FRAMECHANGED);
1399     }
1400     else
1401     {
1402     HMENU hMenu;
1403    
1404     hMenu = GetMenu(FILEHASH_parent_thread_main_window_handle);
1405     FILEHASH_always_on_top = 1;
1406     CheckMenuItem(hMenu, ID_OPTIONS_WINDOWALWAYSONTOP, MF_CHECKED);
1407     SetWindowPos(FILEHASH_parent_thread_main_window_handle,
1408     HWND_TOPMOST,
1409     0,
1410     0,
1411     0,
1412     0,
1413     SWP_NOMOVE | SWP_NOSIZE | SWP_FRAMECHANGED);
1414     }
1415     return 0;
1416     }
1417     case ID_HELP_ABOUT:
1418     case ID_HELP_HELP:
1419     {
1420     char *msg;
1421     char *first_line = "FILEHASH, Copyright \xA9 2010 David T. Ashley\n\n";
1422     char *second_line = "This program is provided under the GNU General Public License, Version 3, and comes with ABSOLUTELY NO WARRANTY.\n\n";
1423     char *third_line = "This is free software, and you are welcome to redistribute it. For a copy of the source code and license or to inquire "
1424     "about technical matters, please write to "
1425     "David T. Ashley (dashley@gmail.com).\n\n";
1426     char *fourth_line = "[Built on " __DATE__ " at " __TIME__ "]";
1427    
1428     msg = malloc(
1429     strlen(first_line) +
1430     strlen(second_line) +
1431     strlen(third_line) +
1432     strlen(fourth_line) +
1433     1);
1434    
1435     assert(msg != NULL);
1436    
1437     if (msg)
1438     {
1439     strcpy_s(msg, strlen(first_line)+strlen(second_line)+strlen(third_line)+strlen(fourth_line)+1, first_line);
1440     strcat_s(msg, strlen(first_line)+strlen(second_line)+strlen(third_line)+strlen(fourth_line)+1, second_line);
1441     strcat_s(msg, strlen(first_line)+strlen(second_line)+strlen(third_line)+strlen(fourth_line)+1, third_line);
1442     strcat_s(msg, strlen(first_line)+strlen(second_line)+strlen(third_line)+strlen(fourth_line)+1, fourth_line);
1443     MessageBox (hwnd,
1444     msg,
1445     FILEHASH_szAppName,
1446     MB_OK|MB_ICONINFORMATION) ;
1447     free(msg);
1448     }
1449     return 0 ;
1450     }
1451     }
1452     break;
1453     }
1454     }
1455    
1456     return DefWindowProc (hwnd, message, wParam, lParam) ;
1457     }
1458    
1459    
1460     //This is the child thread which is started in order to calculate the SHA-512
1461     //of a single group of files. This is done because a single-threaded approach
1462     //does not allow the GUI to continue to receive Windows events, and it
1463     //clogs up the desktop with an unmoveable unresponsive blob. This child
1464     //thread keeps its eye on the abort flag, and will terminate if it sees that.
1465     //It takes its input from the top of the list of filenames, and returns
1466     //the SHA-512, which takes some time to compute.
1467     //
1468     static unsigned __stdcall FILEHASH_ChildThreadFunc(void *pArguments)
1469     {
1470     int fidx;
1471     //The index of the table entry we're currently processing.
1472     DWORD file_attributes;
1473     //The returned file attributes from the OS.
1474     HANDLE hFile = (HANDLE) -1;
1475     //The file handle used to get size and to open for reading. This being
1476     //not the error value signals that it is valid and will need to be closed.
1477     DWORD file_size=0;
1478     //File size obtained from a call to the GetFileSize() function.
1479     DWORD file_size_high=0;
1480     //High 32 bits of same.
1481     DWORD last_error=0;
1482     //Result of the GetLastError() function. This is required to properly decode
1483     //the file size when very large files are involved.
1484     DWORD rc = 0;
1485     //Return code from file seek.
1486     BOOL rv = 0;
1487    
1488     struct FILEHASH_SHA512_Sha512StateStruct sha512s;
1489     struct FILEHASH_SHA512_Sha512ResultStruct sha512r;
1490     int exit_flag = 0;
1491     DWORD bytes_read = 0;
1492    
1493    
1494     //We have been invoked. We now just signature files until the list is
1495     //done or until we are asked to gracefully abort.
1496     for (
1497     fidx = 0;
1498     (fidx<FILEHASH_MAXFILES) && (FILEHASH_file_info.file_info[fidx].fpath[0] != 0) && (!FILEHASH_thread_abort_request);
1499     fidx++
1500     )
1501     {
1502     //Set any values here that are critical to have right in case we must abort.
1503     hFile = (HANDLE) -1;
1504     //This has to be the error value. If we abort, need to know whether
1505     //to try to close this.
1506    
1507     /********************************************************************************/
1508     /********************************************************************************/
1509     /******* F I L E A T T R I B U T E S ***************************************/
1510     /********************************************************************************/
1511     /********************************************************************************/
1512     file_attributes = GetFileAttributes((char *)FILEHASH_file_info.file_info[fidx].fpath);
1513     if (file_attributes == 0xFFFFFFFF)
1514     {
1515     FILEHASH_file_info.file_info[fidx].is_directory_error = 1;
1516     //Signal trouble trying to figure out if this is a directory. This also
1517     //signals that the OS does not understand the file path, so can't do much.
1518     }
1519     else if (file_attributes & FILE_ATTRIBUTE_DIRECTORY)
1520     {
1521     FILEHASH_file_info.file_info[fidx].is_directory = 1;
1522     //This is a directory.
1523     }
1524    
1525     //In any case, the is_directory information is now valid.
1526     FILEHASH_file_info.file_info[fidx].is_directory_valid = 1;
1527    
1528     /********************************************************************************/
1529     /********************************************************************************/
1530     /******* F I L E S I Z E ***************************************************/
1531     /********************************************************************************/
1532     /********************************************************************************/
1533     //If this is a directory or if there was an error getting information, we
1534     //cannot go forward with finding file size information.
1535     if (FILEHASH_file_info.file_info[fidx].is_directory || FILEHASH_file_info.file_info[fidx].is_directory_error)
1536     {
1537     FILEHASH_file_info.file_info[fidx].file_size_error = 1;
1538     }
1539     else
1540     {
1541     hFile = CreateFile ((char *)FILEHASH_file_info.file_info[fidx].fpath,
1542     GENERIC_READ,
1543     FILE_SHARE_READ | FILE_SHARE_WRITE,
1544     NULL,
1545     OPEN_EXISTING,
1546     FILE_ATTRIBUTE_NORMAL | FILE_FLAG_SEQUENTIAL_SCAN,
1547     (HANDLE)NULL);
1548     //Try to open the file to look at it. The documentation
1549     //of the CreateFile() call is misleading in the MSDN help.
1550     //A web reference said that the flag combination above,
1551     //
1552     // FILE_SHARE_READ | FILE_SHARE_WRITE,
1553     //
1554     //means "exclude none", i.e. allow others to have file open for both read
1555     //and write. This seems to be the right combination to allow
1556     //the signaturing of documents that are open with Microsoft
1557     //Word or other applications. I have no idea what will happen
1558     //if the file size changes while the file is open, but I
1559     //assume that the EOF will become true or there will be an error,
1560     //either of which will terminate processing of the file.
1561     if (hFile == (HANDLE) -1)
1562     {
1563     //Open error. Can't go further.
1564     FILEHASH_file_info.file_info[fidx].file_size_error = 1;
1565     }
1566     else
1567     {
1568     //Try to obtain the file size.
1569     file_size = GetFileSize(hFile, &file_size_high);
1570    
1571     //Try to get the error flags, which we may need.
1572     last_error = GetLastError();
1573    
1574     //There is some voodoo involved with file size and the
1575     //error code. This is documented in the GetFileSize() docs.
1576     if ((file_size == 0xFFFFFFFF) && (last_error != NO_ERROR))
1577     {
1578     FILEHASH_file_info.file_info[fidx].file_size_error = 1;
1579     }
1580     else
1581     {
1582     unsigned __int64 lo, hi, composite;
1583     //If we're here, we have a clean size. Convert it and display it.
1584    
1585     //Play the bit games to get the size.
1586     lo = (unsigned __int64)file_size;
1587     hi = (unsigned __int64)file_size_high;
1588     composite = lo + (hi << 32);
1589     FILEHASH_file_info.file_info[fidx].file_size = composite;
1590     }
1591     }
1592     }
1593    
1594     //The file size information is now valid in any case.
1595     FILEHASH_file_info.file_info[fidx].file_size_valid = 1;
1596    
1597     //At this point there is potentially progress to report to
1598     //the main thread. We will sit and spin until the main
1599     //thread will accept a posted event announcing progress
1600     //or until we are aborted.
1601     while (!PostMessage(FILEHASH_parent_thread_main_window_handle,
1602     WM_USER_EV_CHILD_THREAD_PROGRESS,
1603     0,
1604     0)
1605     &&
1606     !FILEHASH_thread_abort_request)
1607     {
1608     Sleep(1000); //Wait 1 second until trying again.
1609     //1000ms is a long time for a modern computer,
1610     //and this should be OK to ease the load if
1611     //the system is encountering performance difficulties.
1612     }
1613    
1614     /********************************************************************************/
1615     /********************************************************************************/
1616     /******* S H A - 5 1 2 *******************************************************/
1617     /********************************************************************************/
1618     /********************************************************************************/
1619     if (hFile == (HANDLE) -1)
1620     {
1621     //File handle signals an error condition. We cannot
1622     //even read the file for SHA-512. Just set info
1623     //and boogie.
1624     strcpy_s((char *)FILEHASH_file_info.file_info[fidx].sha512, sizeof(FILEHASH_file_info.file_info[fidx].sha512), "INVALID FILE HANDLE");
1625     }
1626     else
1627     {
1628     //This is the meat of the matter where we read the file contents and do
1629     //the hash calculations. The assumption made is the the buffer size
1630     //will be somewhere in the range of 16K-1M, so that the time to process
1631     //that much data is fairly small. This should be enough granularity
1632     //for a graceful voluntary thread abort.
1633     //
1634     //Rewind the file to positon 0.
1635     rc = SetFilePointer(hFile, 0, NULL, FILE_BEGIN);
1636     if (rc == 0xFFFFFFFF)
1637     {
1638     strcpy_s((char *)FILEHASH_file_info.file_info[fidx].sha512, sizeof(FILEHASH_file_info.file_info[fidx].sha512), "FILE SEEK ERROR");
1639     goto file_read_loop_endpoint;
1640     }
1641    
1642     //Initialize the SHA512 state block.
1643     FILEHASH_SHA512_Sha512StateStructOpen(&sha512s);
1644    
1645     //Iterate through, reading the file and processing the blocks. In the case
1646     //of an abort, we assign the strings appropriately.
1647     exit_flag = 0;
1648     while (!exit_flag)
1649     {
1650     rv = ReadFile(hFile, FILEHASH_file_read_buf, FILEHASH_FILE_READ_BUF_SIZE, &bytes_read, NULL);
1651    
1652     //Add whatever has been read to the running calculation.
1653     if (bytes_read)
1654     {
1655     FILEHASH_SHA512_Sha512StateStructAddData(&sha512s, FILEHASH_file_read_buf, bytes_read);
1656     }
1657    
1658     //Process error conditions.
1659     if (!rv)
1660     {
1661     strcpy_s((char *)FILEHASH_file_info.file_info[fidx].sha512, sizeof(FILEHASH_file_info.file_info[fidx].sha512), "FILE READ ERROR");
1662     goto file_read_loop_endpoint;
1663     }
1664    
1665     if (!bytes_read)
1666     {
1667     //This is the no-error abort when we hit the end of the file naturally.
1668     exit_flag = 1;
1669     }
1670     else if (FILEHASH_thread_abort_request)
1671     {
1672     strcpy_s((char *)FILEHASH_file_info.file_info[fidx].sha512, sizeof(FILEHASH_file_info.file_info[fidx].sha512), "OPERATION ABORTED");
1673     goto file_read_loop_endpoint;
1674     }
1675     }
1676    
1677     //This is the natural fallthrough when there was no error.
1678     //
1679     //Close up the SHA-512 structure.
1680     FILEHASH_SHA512_Sha512StateStructClose(&sha512s, &sha512r);
1681    
1682     //Form up an SHA-512 string.
1683     strcpy_s((char *)FILEHASH_file_info.file_info[fidx].sha512, sizeof(FILEHASH_file_info.file_info[fidx].sha512), sha512r.sha512_chars);
1684    
1685     //Report progress to parent thread.
1686     while (!PostMessage(FILEHASH_parent_thread_main_window_handle,
1687     WM_USER_EV_CHILD_THREAD_PROGRESS,
1688     0,
1689     0))
1690     {
1691     Sleep(1000); //Wait 1 second until trying again.
1692     }
1693    
1694     file_read_loop_endpoint: ;
1695     }
1696    
1697     //In any case both CRC32 and MD5 info filled in.
1698     FILEHASH_file_info.file_info[fidx].sha512_valid = 1;
1699    
1700     //If the file handle is valid (i.e. we opened the file) we must
1701     //close it, regardless of cause.
1702     if (hFile != (HANDLE)-1)
1703     {
1704     BOOL close_result;
1705    
1706     close_result = CloseHandle(hFile);
1707    
1708     if (!close_result)
1709     {
1710     strcpy_s((char *)FILEHASH_file_info.file_info[fidx].sha512, sizeof(FILEHASH_file_info.file_info[fidx].sha512), "FILE HANDLE CLOSE ERROR");
1711     }
1712     }
1713     } // End for() each table entry loop.
1714    
1715    
1716     //Report completion to parent thread.
1717     if (FILEHASH_thread_abort_request)
1718     FILEHASH_file_info.aborted = 1;
1719     else
1720     FILEHASH_file_info.terminated_normally = 1;
1721    
1722     while (!PostMessage(FILEHASH_parent_thread_main_window_handle,
1723     WM_USER_EV_CHILD_THREAD_ENDING,
1724     0,
1725     0))
1726     {
1727     Sleep(1000); //Wait 1 second until trying again.
1728     }
1729    
1730     return 0;
1731     }
1732    
1733    
1734     //This function does a hard sync stop on the child thread if it is running.
1735     //If not running, returns immediately. Because the time to CRC32 or MD5 a
1736     //single buffer is negligible, it shouldn't take long for the thread to
1737     //gracefully end itself.
1738     //
1739     static void FILEHASH_ChildThreadHardSyncStop(void)
1740     {
1741     if (FILEHASH_child_thread_is_active)
1742     {
1743     HMENU hMenu;
1744    
1745     FILEHASH_thread_abort_request = 1;
1746    
1747     WaitForSingleObject(FILEHASH_child_handle, INFINITE);
1748    
1749     //The thread is done.
1750     FILEHASH_child_thread_is_active = 0;
1751     FILEHASH_thread_abort_request = 0;
1752     FILEHASH_child_handle = 0;
1753    
1754     hMenu = GetMenu(FILEHASH_parent_thread_main_window_handle);
1755    
1756     EnableMenuItem(hMenu, ID_ACTIONS_HALTSIGOP, MF_GRAYED);
1757     }
1758     }
1759    
1760    
1761     //Starts up a child thread.
1762     //
1763     static void FILEHASH_ChildThreadStart(void)
1764     {
1765     unsigned thread_id;
1766     //We just discard this.
1767    
1768     //We don't dare start up our single child thread unless none is already running.
1769     //In the release version, such an error is just ignored, but in the debug version,
1770     //hard stop.
1771     assert(!FILEHASH_child_thread_is_active);
1772    
1773     if (!FILEHASH_child_thread_is_active)
1774     {
1775     //Test compilation of second thread invocation.
1776     FILEHASH_child_handle = (HANDLE) _beginthreadex(NULL,
1777     0,
1778     &FILEHASH_ChildThreadFunc,
1779     NULL,
1780     0,
1781     &thread_id);
1782     if (!FILEHASH_child_handle)
1783     {
1784     //This is an error return from _beginthreadex.
1785     assert(0);
1786     }
1787     else
1788     {
1789     HMENU hMenu;
1790    
1791     FILEHASH_child_thread_is_active = 1;
1792    
1793     hMenu = GetMenu(FILEHASH_parent_thread_main_window_handle);
1794    
1795     EnableMenuItem(hMenu, ID_ACTIONS_HALTSIGOP, MF_ENABLED);
1796     }
1797     }
1798     }
1799    
1800    
1801     //Makes a generic sound to alert user. Honors the FILEHASH_use_sound state.
1802     //
1803     static void FILEHASH_MakeGenericSound(void)
1804     {
1805     if (FILEHASH_use_sound)
1806     {
1807     MessageBeep(MB_ICONEXCLAMATION);
1808     }
1809     }
1810    
1811    
1812     //----------------------------------------------------------------------------------------------------
1813     // GNU GENERAL PUBLIC LICENSE
1814     // Version 3, 29 June 2007
1815     //
1816     // Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
1817     // Everyone is permitted to copy and distribute verbatim copies
1818     // of this license document, but changing it is not allowed.
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1820     // Preamble
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1830     //GNU General Public License for most of our software; it applies also to
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2145     //network may be denied when the modification itself materially and
2146     //adversely affects the operation of the network or violates the rules and
2147     //protocols for communication across the network.
2148     //
2149     // Corresponding Source conveyed, and Installation Information provided,
2150     //in accord with this section must be in a format that is publicly
2151     //documented (and with an implementation available to the public in
2152     //source code form), and must require no special password or key for
2153     //unpacking, reading or copying.
2154     //
2155     // 7. Additional Terms.
2156     //
2157     // "Additional permissions" are terms that supplement the terms of this
2158     //License by making exceptions from one or more of its conditions.
2159     //Additional permissions that are applicable to the entire Program shall
2160     //be treated as though they were included in this License, to the extent
2161     //that they are valid under applicable law. If additional permissions
2162     //apply only to part of the Program, that part may be used separately
2163     //under those permissions, but the entire Program remains governed by
2164     //this License without regard to the additional permissions.
2165     //
2166     // When you convey a copy of a covered work, you may at your option
2167     //remove any additional permissions from that copy, or from any part of
2168     //it. (Additional permissions may be written to require their own
2169     //removal in certain cases when you modify the work.) You may place
2170     //additional permissions on material, added by you to a covered work,
2171     //for which you have or can give appropriate copyright permission.
2172     //
2173     // Notwithstanding any other provision of this License, for material you
2174     //add to a covered work, you may (if authorized by the copyright holders of
2175     //that material) supplement the terms of this License with terms:
2176     //
2177     // a) Disclaiming warranty or limiting liability differently from the
2178     // terms of sections 15 and 16 of this License; or
2179     //
2180     // b) Requiring preservation of specified reasonable legal notices or
2181     // author attributions in that material or in the Appropriate Legal
2182     // Notices displayed by works containing it; or
2183     //
2184     // c) Prohibiting misrepresentation of the origin of that material, or
2185     // requiring that modified versions of such material be marked in
2186     // reasonable ways as different from the original version; or
2187     //
2188     // d) Limiting the use for publicity purposes of names of licensors or
2189     // authors of the material; or
2190     //
2191     // e) Declining to grant rights under trademark law for use of some
2192     // trade names, trademarks, or service marks; or
2193     //
2194     // f) Requiring indemnification of licensors and authors of that
2195     // material by anyone who conveys the material (or modified versions of
2196     // it) with contractual assumptions of liability to the recipient, for
2197     // any liability that these contractual assumptions directly impose on
2198     // those licensors and authors.
2199     //
2200     // All other non-permissive additional terms are considered "further
2201     //restrictions" within the meaning of section 10. If the Program as you
2202     //received it, or any part of it, contains a notice stating that it is
2203     //governed by this License along with a term that is a further
2204     //restriction, you may remove that term. If a license document contains
2205     //a further restriction but permits relicensing or conveying under this
2206     //License, you may add to a covered work material governed by the terms
2207     //of that license document, provided that the further restriction does
2208     //not survive such relicensing or conveying.
2209     //
2210     // If you add terms to a covered work in accord with this section, you
2211     //must place, in the relevant source files, a statement of the
2212     //additional terms that apply to those files, or a notice indicating
2213     //where to find the applicable terms.
2214     //
2215     // Additional terms, permissive or non-permissive, may be stated in the
2216     //form of a separately written license, or stated as exceptions;
2217     //the above requirements apply either way.
2218     //
2219     // 8. Termination.
2220     //
2221     // You may not propagate or modify a covered work except as expressly
2222     //provided under this License. Any attempt otherwise to propagate or
2223     //modify it is void, and will automatically terminate your rights under
2224     //this License (including any patent licenses granted under the third
2225     //paragraph of section 11).
2226     //
2227     // However, if you cease all violation of this License, then your
2228     //license from a particular copyright holder is reinstated (a)
2229     //provisionally, unless and until the copyright holder explicitly and
2230     //finally terminates your license, and (b) permanently, if the copyright
2231     //holder fails to notify you of the violation by some reasonable means
2232     //prior to 60 days after the cessation.
2233     //
2234     // Moreover, your license from a particular copyright holder is
2235     //reinstated permanently if the copyright holder notifies you of the
2236     //violation by some reasonable means, this is the first time you have
2237     //received notice of violation of this License (for any work) from that
2238     //copyright holder, and you cure the violation prior to 30 days after
2239     //your receipt of the notice.
2240     //
2241     // Termination of your rights under this section does not terminate the
2242     //licenses of parties who have received copies or rights from you under
2243     //this License. If your rights have been terminated and not permanently
2244     //reinstated, you do not qualify to receive new licenses for the same
2245     //material under section 10.
2246     //
2247     // 9. Acceptance Not Required for Having Copies.
2248     //
2249     // You are not required to accept this License in order to receive or
2250     //run a copy of the Program. Ancillary propagation of a covered work
2251     //occurring solely as a consequence of using peer-to-peer transmission
2252     //to receive a copy likewise does not require acceptance. However,
2253     //nothing other than this License grants you permission to propagate or
2254     //modify any covered work. These actions infringe copyright if you do
2255     //not accept this License. Therefore, by modifying or propagating a
2256     //covered work, you indicate your acceptance of this License to do so.
2257     //
2258     // 10. Automatic Licensing of Downstream Recipients.
2259     //
2260     // Each time you convey a covered work, the recipient automatically
2261     //receives a license from the original licensors, to run, modify and
2262     //propagate that work, subject to this License. You are not responsible
2263     //for enforcing compliance by third parties with this License.
2264     //
2265     // An "entity transaction" is a transaction transferring control of an
2266     //organization, or substantially all assets of one, or subdividing an
2267     //organization, or merging organizations. If propagation of a covered
2268     //work results from an entity transaction, each party to that
2269     //transaction who receives a copy of the work also receives whatever
2270     //licenses to the work the party's predecessor in interest had or could
2271     //give under the previous paragraph, plus a right to possession of the
2272     //Corresponding Source of the work from the predecessor in interest, if
2273     //the predecessor has it or can get it with reasonable efforts.
2274     //
2275     // You may not impose any further restrictions on the exercise of the
2276     //rights granted or affirmed under this License. For example, you may
2277     //not impose a license fee, royalty, or other charge for exercise of
2278     //rights granted under this License, and you may not initiate litigation
2279     //(including a cross-claim or counterclaim in a lawsuit) alleging that
2280     //any patent claim is infringed by making, using, selling, offering for
2281     //sale, or importing the Program or any portion of it.
2282     //
2283     // 11. Patents.
2284     //
2285     // A "contributor" is a copyright holder who authorizes use under this
2286     //License of the Program or a work on which the Program is based. The
2287     //work thus licensed is called the contributor's "contributor version".
2288     //
2289     // A contributor's "essential patent claims" are all patent claims
2290     //owned or controlled by the contributor, whether already acquired or
2291     //hereafter acquired, that would be infringed by some manner, permitted
2292     //by this License, of making, using, or selling its contributor version,
2293     //but do not include claims that would be infringed only as a
2294     //consequence of further modification of the contributor version. For
2295     //purposes of this definition, "control" includes the right to grant
2296     //patent sublicenses in a manner consistent with the requirements of
2297     //this License.
2298     //
2299     // Each contributor grants you a non-exclusive, worldwide, royalty-free
2300     //patent license under the contributor's essential patent claims, to
2301     //make, use, sell, offer for sale, import and otherwise run, modify and
2302     //propagate the contents of its contributor version.
2303     //
2304     // In the following three paragraphs, a "patent license" is any express
2305     //agreement or commitment, however denominated, not to enforce a patent
2306     //(such as an express permission to practice a patent or covenant not to
2307     //sue for patent infringement). To "grant" such a patent license to a
2308     //party means to make such an agreement or commitment not to enforce a
2309     //patent against the party.
2310     //
2311     // If you convey a covered work, knowingly relying on a patent license,
2312     //and the Corresponding Source of the work is not available for anyone
2313     //to copy, free of charge and under the terms of this License, through a
2314     //publicly available network server or other readily accessible means,
2315     //then you must either (1) cause the Corresponding Source to be so
2316     //available, or (2) arrange to deprive yourself of the benefit of the
2317     //patent license for this particular work, or (3) arrange, in a manner
2318     //consistent with the requirements of this License, to extend the patent
2319     //license to downstream recipients. "Knowingly relying" means you have
2320     //actual knowledge that, but for the patent license, your conveying the
2321     //covered work in a country, or your recipient's use of the covered work
2322     //in a country, would infringe one or more identifiable patents in that
2323     //country that you have reason to believe are valid.
2324     //
2325     // If, pursuant to or in connection with a single transaction or
2326     //arrangement, you convey, or propagate by procuring conveyance of, a
2327     //covered work, and grant a patent license to some of the parties
2328     //receiving the covered work authorizing them to use, propagate, modify
2329     //or convey a specific copy of the covered work, then the patent license
2330     //you grant is automatically extended to all recipients of the covered
2331     //work and works based on it.
2332     //
2333     // A patent license is "discriminatory" if it does not include within
2334     //the scope of its coverage, prohibits the exercise of, or is
2335     //conditioned on the non-exercise of one or more of the rights that are
2336     //specifically granted under this License. You may not convey a covered
2337     //work if you are a party to an arrangement with a third party that is
2338     //in the business of distributing software, under which you make payment
2339     //to the third party based on the extent of your activity of conveying
2340     //the work, and under which the third party grants, to any of the
2341     //parties who would receive the covered work from you, a discriminatory
2342     //patent license (a) in connection with copies of the covered work
2343     //conveyed by you (or copies made from those copies), or (b) primarily
2344     //for and in connection with specific products or compilations that
2345     //contain the covered work, unless you entered into that arrangement,
2346     //or that patent license was granted, prior to 28 March 2007.
2347     //
2348     // Nothing in this License shall be construed as excluding or limiting
2349     //any implied license or other defenses to infringement that may
2350     //otherwise be available to you under applicable patent law.
2351     //
2352     // 12. No Surrender of Others' Freedom.
2353     //
2354     // If conditions are imposed on you (whether by court order, agreement or
2355     //otherwise) that contradict the conditions of this License, they do not
2356     //excuse you from the conditions of this License. If you cannot convey a
2357     //covered work so as to satisfy simultaneously your obligations under this
2358     //License and any other pertinent obligations, then as a consequence you may
2359     //not convey it at all. For example, if you agree to terms that obligate you
2360     //to collect a royalty for further conveying from those to whom you convey
2361     //the Program, the only way you could satisfy both those terms and this
2362     //License would be to refrain entirely from conveying the Program.
2363     //
2364     // 13. Use with the GNU Affero General Public License.
2365     //
2366     // Notwithstanding any other provision of this License, you have
2367     //permission to link or combine any covered work with a work licensed
2368     //under version 3 of the GNU Affero General Public License into a single
2369     //combined work, and to convey the resulting work. The terms of this
2370     //License will continue to apply to the part which is the covered work,
2371     //but the special requirements of the GNU Affero General Public License,
2372     //section 13, concerning interaction through a network will apply to the
2373     //combination as such.
2374     //
2375     // 14. Revised Versions of this License.
2376     //
2377     // The Free Software Foundation may publish revised and/or new versions of
2378     //the GNU General Public License from time to time. Such new versions will
2379     //be similar in spirit to the present version, but may differ in detail to
2380     //address new problems or concerns.
2381     //
2382     // Each version is given a distinguishing version number. If the
2383     //Program specifies that a certain numbered version of the GNU General
2384     //Public License "or any later version" applies to it, you have the
2385     //option of following the terms and conditions either of that numbered
2386     //version or of any later version published by the Free Software
2387     //Foundation. If the Program does not specify a version number of the
2388     //GNU General Public License, you may choose any version ever published
2389     //by the Free Software Foundation.
2390     //
2391     // If the Program specifies that a proxy can decide which future
2392     //versions of the GNU General Public License can be used, that proxy's
2393     //public statement of acceptance of a version permanently authorizes you
2394     //to choose that version for the Program.
2395     //
2396     // Later license versions may give you additional or different
2397     //permissions. However, no additional obligations are imposed on any
2398     //author or copyright holder as a result of your choosing to follow a
2399     //later version.
2400     //
2401     // 15. Disclaimer of Warranty.
2402     //
2403     // THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
2404     //APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
2405     //HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
2406     //OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
2407     //THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
2408     //PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
2409     //IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
2410     //ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
2411     //
2412     // 16. Limitation of Liability.
2413     //
2414     // IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
2415     //WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
2416     //THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
2417     //GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
2418     //USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
2419     //DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
2420     //PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
2421     //EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
2422     //SUCH DAMAGES.
2423     //
2424     // 17. Interpretation of Sections 15 and 16.
2425     //
2426     // If the disclaimer of warranty and limitation of liability provided
2427     //above cannot be given local legal effect according to their terms,
2428     //reviewing courts shall apply local law that most closely approximates
2429     //an absolute waiver of all civil liability in connection with the
2430     //Program, unless a warranty or assumption of liability accompanies a
2431     //copy of the Program in return for a fee.
2432     //
2433     // END OF TERMS AND CONDITIONS
2434     //
2435     // How to Apply These Terms to Your New Programs
2436     //
2437     // If you develop a new program, and you want it to be of the greatest
2438     //possible use to the public, the best way to achieve this is to make it
2439     //free software which everyone can redistribute and change under these terms.
2440     //
2441     // To do so, attach the following notices to the program. It is safest
2442     //to attach them to the start of each source file to most effectively
2443     //state the exclusion of warranty; and each file should have at least
2444     //the "copyright" line and a pointer to where the full notice is found.
2445     //
2446     // <one line to give the program's name and a brief idea of what it does.>
2447     // Copyright (C) <year> <name of author>
2448     //
2449     // This program is free software: you can redistribute it and/or modify
2450     // it under the terms of the GNU General Public License as published by
2451     // the Free Software Foundation, either version 3 of the License, or
2452     // (at your option) any later version.
2453     //
2454     // This program is distributed in the hope that it will be useful,
2455     // but WITHOUT ANY WARRANTY; without even the implied warranty of
2456     // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
2457     // GNU General Public License for more details.
2458     //
2459     // You should have received a copy of the GNU General Public License
2460     // along with this program. If not, see <http://www.gnu.org/licenses/>.
2461     //
2462     //Also add information on how to contact you by electronic and paper mail.
2463     //
2464     // If the program does terminal interaction, make it output a short
2465     //notice like this when it starts in an interactive mode:
2466     //
2467     // <program> Copyright (C) <year> <name of author>
2468     // This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
2469     // This is free software, and you are welcome to redistribute it
2470     // under certain conditions; type `show c' for details.
2471     //
2472     //The hypothetical commands `show w' and `show c' should show the appropriate
2473     //parts of the General Public License. Of course, your program's commands
2474     //might be different; for a GUI interface, you would use an "about box".
2475     //
2476     // You should also get your employer (if you work as a programmer) or school,
2477     //if any, to sign a "copyright disclaimer" for the program, if necessary.
2478     //For more information on this, and how to apply and follow the GNU GPL, see
2479     //<http://www.gnu.org/licenses/>.
2480     //
2481     // The GNU General Public License does not permit incorporating your program
2482     //into proprietary programs. If your program is a subroutine library, you
2483     //may consider it more useful to permit linking proprietary applications with
2484     //the library. If this is what you want to do, use the GNU Lesser General
2485     //Public License instead of this License. But first, please read
2486     //<http://www.gnu.org/philosophy/why-not-lgpl.html>.
2487     //----------------------------------------------------------------------------------------------------
2488     // End of FILEHASH.C. */
2489     //----------------------------------------------------------------------------------------------------
2490    

dashley@gmail.com
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